KR101959655B1 - Aluminum alloy strand, aluminum alloy strand and its manufacturing method, automobile wire and wire harness - Google Patents

Abstract

The aluminum alloy wire 10 is selected from the group consisting of Cu, Cr, Ni, and Zr in an amount of 0.3 to 0.9% of Mg, 0.1 to 0.7% of Si, 0.1 to 0.4% : 0.01% or more and 0.5% or less in total, and the remainder has a chemical composition of Al and inevitable impurities. The surface roughness Ra of the non-contact type surface roughness tester is from 0.15 탆 to 2 탆. The aluminum alloy strand (1) has a plurality of aluminum alloy strands (10) twisted together. The automotive wire (2) has an aluminum alloy strand (1). The wire harness 3 has an automobile electric wire 2 and a terminal 30 which is pressed onto the aluminum alloy strand 1 of the automobile electric wire 2.

Description

Aluminum alloy strand, aluminum alloy strand and its manufacturing method, automobile wire and wire harness

The present invention relates to an aluminum alloy wire, an aluminum alloy wire and a manufacturing method thereof, an automobile electric wire and a wire harness.

BACKGROUND ART Conventionally, an aluminum alloy strand having a plurality of strands of aluminum alloy wires twisted together is known. Further, automobile wires having aluminum alloy stranded wires are known. Also known are automobile wires and wire harnesses having terminals pressed onto aluminum alloy strands of automobile wires.

Prior art 1 discloses a technique for pressing a terminal to a folded portion where the tip of an aluminum core wire is folded back to improve a terminal fixing force.

Patent Document 1: JP-A-2009-266469

However, the prior art needs to form a folded portion, which is not practical because the pressing process is increased. In addition, when the terminal is pressed against the aluminum alloy strand without forming the folded portion, even if the contact resistance between the aluminum alloy strand and the terminal is good, the aluminum alloy strand in the inner layer of the aluminum alloy strand is dislocated, Is lowered.

SUMMARY OF THE INVENTION The present invention has been made in view of such a background, and an object of the present invention is to provide an aluminum alloy wire, an aluminum alloy wire, an automobile wire and a wire harness which can improve a terminal fixing force.

One aspect of the present invention is an aluminum alloy wire used in a conductor of an automotive wire,

0.3% by mass or more and 0.9% by mass or less of Mg,

Si: 0.1 mass% or more and 0.7 mass% or less,

Fe: 0.1 mass% or more and 0.4 mass% or less,

At least one element selected from the group consisting of Cu, Cr, Ni and Zr: 0.01 mass% or more and 0.5 mass% or less in total

≪ / RTI >

The remainder having a chemical composition of Al and inevitable impurities,

Wherein the surface roughness Ra of the non-contact type surface roughness tester is in the range of 0.15 탆 to 2 탆.

Another aspect of the present invention is an aluminum alloy strand characterized in that a plurality of said aluminum alloy strands are twisted together.

Another aspect of the present invention is an automobile electric wire characterized by having the aluminum alloy strand.

Another aspect of the present invention is a wire harness comprising the automobile wire and the terminals pressed onto the aluminum alloy strand of the automobile wire.

According to another aspect of the present invention, there is provided a method of manufacturing an aluminum alloy strand used in a conductor of an automotive wire,

0.3% by mass or more and 0.9% by mass or less of Mg,

Si: 0.1 mass% or more and 0.7 mass% or less,

Fe: 0.1 mass% or more and 0.4 mass% or less,

At least one element selected from the group consisting of Cu, Cr, Ni and Zr: 0.01 mass% or more and 0.5 mass% or less in total

≪ / RTI >

A casting step of forming a casting material having a chemical component composition consisting of Al and inevitable impurities,

A whole body process for forming a body material by subjecting the cast material to a plastic working process,

A drawing step of forming a drawing material by drawing on the whole body material,

A twisting process in which a plurality of the drawing members are twisted to form a drawn wire member, a heat treatment is applied to the drawn wire member or a heat treatment is applied to the drawn member, and a plurality of the heat-

Lt; / RTI &

By the drawing process, the surface roughness Ra of the drawing material measured by the non-contact type surface roughness measuring device is set to 0.15 탆 or more and 2 탆 or less,

Wherein the surface roughness Ra of the drawing material is 0.15 탆 or more and 2 탆 or less by the non-contact type surface roughness tester after the drawing process, before forming the drawing material. There is a way.

The aluminum alloy wire has the aforementioned specific chemical composition and the surface roughness Ra of the non-contact type surface roughness meter is within a specific range. In the aluminum alloy strand, a plurality of the aluminum alloy strands are twisted together. Further, the automobile electric wire has the aluminum alloy strand. Further, the wire harness has the automobile electric wire and the terminal pressed on the aluminum alloy wire of the automobile electric wire.

Therefore, the aluminum alloy wire, the aluminum alloy wire, the automobile wire and the wire harness can improve the terminal fixing force. This is because when the surface of the aluminum alloy strand having the specific chemical component composition has a surface roughness Ra in a specific range, when the terminal is pressed on the strand of the aluminum alloy strand, the distance between the aluminum alloy strands existing in the inner strand of the aluminum alloy strand The frictional force is increased, and the sliding of the aluminum alloy element wires is suppressed. As a result, the aluminum alloy element wire of the inner layer is hardly released.

In addition, the above-described method for manufacturing the aluminum alloy strand includes the respective steps described above. Therefore, it is possible to obtain the above-described aluminum alloy strand capable of improving the terminal securing force.

1 is an explanatory view showing an aluminum alloy wire, an aluminum alloy wire, an automobile wire and a wire harness according to the first embodiment.
2 is an explanatory view showing a crimp height (C / H) at the time of terminal crimping in the first embodiment.

The reason for limiting the chemical composition in the aluminum alloy wire will be described.

- Mg: 0.3 mass% or more and 0.9 mass% or less, Si: 0.1 mass% or more and 0.7 mass% or less

By containing 0.3 mass% or more of Mg and 0.1 mass% or more of Si, Mg ₂ Si is precipitated and the strength of the aluminum alloy strand when used for conductors of automobile wires can be secured. When the Mg content exceeds 0.9% by mass and the Si content exceeds 0.7% by mass, the strength of the aluminum alloy strand becomes high, but the conductivity is lowered and breakage is likely to occur at the time of drawing. Therefore, the Mg content is 0.9 mass% or less, and the Si content is 0.7 mass% or less.

The Mg content is preferably 0.35% by mass or more, more preferably 0.4% by mass or more, still more preferably 0.45% by mass or more, and even more preferably 0.5% by mass or more from the viewpoint of improvement of the strength of the aluminum alloy wire can do. The Mg content is preferably 0.85% by mass or less, more preferably 0.8% by mass or less, further preferably 0.75% by mass or less, and still more preferably 0.75% by mass or less, from the viewpoint of the balance between the strength and the electric conductivity of the aluminum alloy wire. May be 0.7 mass% or less.

The Si content is preferably 0.15% by mass or more, more preferably 0.2% by mass or more, still more preferably 0.25% by mass or more, even more preferably 0.3% by mass or more, And more preferably 0.35 mass% or more. The Si content is preferably 0.68 mass% or less, more preferably 0.65 mass% or less, and still more preferably 0.6 mass% or less, from the viewpoint of balance between the strength and the electric conductivity of the aluminum alloy wire.

- Fe: 0.1 mass% or more and 0.4 mass% or less

The higher the Fe content, the higher the strength of the aluminum alloy strand. In order to obtain such an additive effect, the Fe content is 0.1 mass% or more. However, if the Fe content is excessively high, the conductivity and toughness of the aluminum alloy strand deteriorate, and breakage tends to occur at the time of drawing. Therefore, the Fe content is 0.4 mass% or less.

The Fe content is preferably 0.12% by mass or more, and more preferably 0.15% by mass or more, from the viewpoint of improving the strength of the aluminum alloy wire. The Fe content is preferably 0.38 mass% or less, more preferably 0.34 mass% or less, further preferably 0.3 mass% or less, from the viewpoint of securing the conductivity and toughness of the aluminum alloy wire.

- at least one element selected from the group consisting of Cu, Cr, Ni and Zr: 0.01 mass% or more and 0.5 mass% or less in total

Each of the additional elements described above is an element effective for improving the heat resistance and strength of the aluminum alloy wire. In order to obtain the effect of the addition, each of the above-described additive elements is 0.01 mass% or more in total. However, if the total content of each of the additional elements becomes excessively high, the conductivity of the aluminum alloy strand lowers, and breakage tends to occur at the time of drawing. Therefore, the total content of each added element is 0.5 mass% or less.

The total content of each additional element is preferably 0.02% by mass or more, more preferably 0.03% by mass or more, further preferably 0.04% by mass or more, still more preferably 0.04% by mass or more from the viewpoints of heat resistance and strength improvement of the aluminum alloy wire, May be 0.05 mass% or more. The total content of each of the additional elements is preferably 0.45 mass% or less, more preferably 0.4 mass% or less, and still more preferably 0.35 mass% or less, from the viewpoint of securing the conductivity of the aluminum alloy wire.

The chemical composition may further contain Ti and / or B. In this case, the Ti content should be 0.003 mass% or more and 0.03 mass% or less (30 ppm or more and 300 ppm or less in mass ratio) and the B content should be 0.0003 mass% or more and 0.003 mass% or less (3 ppm or more and 30 ppm or less in mass ratio) .

Ti and B are all elements capable of further improving the strength of the aluminum alloy strand. Ti and B have the effect of refining the crystal structure of the aluminum alloy at the time of casting. If the crystal structure is fine, not only the strength of the aluminum alloy wire can be improved but also the drawing workability can be improved. The Ti content is 0.003 mass% or more, and the B content is 0.0003 mass% or more from the viewpoint of sufficiently obtaining the effect of the fine structure of the crystal structure. However, if the Ti content exceeds 0.03 mass% and the B content exceeds 0.003 mass%, the conductivity of the aluminum alloy strand lowers, and the effect of miniaturization of crystal structure is also saturated. Therefore, the Ti content is 0.03 mass% or less, and the B content is 0.003 mass% or less.

The Ti content is preferably 0.005% by mass or more, more preferably 0.007% by mass or more, and even more preferably 0.01% by mass or more, from the viewpoint of promoting miniaturization of the crystal structure. The Ti content is preferably 0.025 mass% or less, and more preferably 0.02 mass% or less, from the viewpoint of securing the conductivity of the aluminum alloy strand. The B content is preferably 0.0005 mass% or more, more preferably 0.001 mass% or more, still more preferably 0.002 mass% or more, still more preferably 0.003 mass% or more, from the viewpoint of promoting miniaturization of the crystal structure . The B content is preferably 0.0025 mass% or less, more preferably 0.002 mass% or less, from the viewpoint of ensuring the conductivity of the aluminum alloy wire.

The aluminum alloy wire has a surface roughness Ra of not less than 0.15 mu m and not more than 2 mu m by a non-contact type surface roughness meter. As a non-contact type surface roughness tester, NewView series manufactured by zygo Co., Ltd. is used.

When the surface roughness Ra is less than 0.15 占 퐉, slippage easily occurs between the aluminum alloy strands present in the inner layer of the strand of aluminum alloy when the terminal is pressed against the strand of aluminum alloy strand. As a result, It becomes easy to fall out. This makes it difficult to improve the terminal fixing force. On the other hand, even if the surface roughness Ra exceeds 2 占 퐉, it is difficult to improve the terminal fixing force.

The surface roughness Ra is preferably not less than 0.16 占 퐉, more preferably not less than 0.17 占 퐉, more preferably not less than 0.18 占 퐉, even more preferably not less than 0.19 占 퐉, And more preferably 0.2 mu m or more. The surface roughness Ra is preferably 1.8 占 퐉 or less, more preferably 1.7 占 퐉 or less, further preferably 1.5 占 퐉 or less, still more preferably 1.3 占 퐉 or less, from the viewpoint of ensuring the effect of improving the terminal securing force, And even more preferably 1 mu m or less.

The wire diameter of the aluminum alloy wire can be 0.1 mm or more and 0.4 mm or less. In this case, it is possible to obtain an aluminum alloy strand which is less likely to be broken due to foreign substances or the like incorporated at the time of manufacture and which has excellent flexural resistance against vibration. In addition, the aluminum alloy wire has good drawability and wire-line workability.

The wire diameter of the aluminum alloy wire may preferably be 0.15 mm or more, more preferably 0.17 mm or more, and further preferably 0.2 mm or more. The wire diameter of the aluminum alloy wire may be preferably 0.35 mm or less, more preferably 0.3 mm or less.

In the aluminum alloy strand, a plurality of the aluminum alloy strands are twisted together. In the aluminum alloy strand, the number of strands of the aluminum alloy strand may be, for example, 7, 11, 19, 37, or the like. In this case, an aluminum alloy strand suitable for use in an automobile engine can be obtained. The number of twists of the aluminum alloy wire is preferably 11, 19 and 37, more preferably 19 and 37, respectively. As the number of kinks increases, the number of aluminum alloy wires in the inner layer increases. Therefore, it is possible to effectively exhibit the above-mentioned action and effect. In particular, when the number of twists is 19 or 37, the above-mentioned action and effect are easily exhibited effectively.

In the aluminum alloy stranded wire, the twist pitch of the aluminum alloy strand may be within a range of 10 to 50 mm, for example. In this case, there is an advantage of improving the endothelial property and improving the productivity of the stranded wire. The twist pitch of the aluminum alloy wire may be preferably 12 mm or more, more preferably 15 mm or more, further preferably 17 mm or more, and even more preferably 20 mm or more. The twist pitch of the aluminum alloy strand may preferably be 48 mm or less, more preferably 45 mm or less, further preferably 43 mm or less, and even more preferably 40 mm or less.

It is preferable that the tensile strength of the aluminum alloy strand is in the range of 200 MPa or more and 350 MPa or less. In this case, an aluminum alloy strand excellent in balance of strength and elongation can be obtained. In addition, it is easy to secure endothelial characteristics against vibration, and is suitable as an aluminum alloy strand used in a vibration environment such as an engine of an automobile.

The tensile strength of the aluminum alloy strand may be preferably 210 MPa or more, more preferably 220 MPa or more, and further preferably 230 MPa or more, from the viewpoint of strength improvement and the like. The tensile strength of the twisted aluminum alloy wire is preferably 330 MPa or less, more preferably 300 MPa or less, and still more preferably 290 MPa or less, from the viewpoint of securing elongation and the like.

The elongation of the aluminum alloy strand is preferably 6% or more. In this case, an aluminum alloy strand that is advantageous for improving toughness can be obtained. The elongation of the aluminum alloy strand may be preferably 7% or more, more preferably 8% or more, further preferably 9% or more, and even more preferably 10% or more. The elongation of the aluminum alloy strand is preferably 15% or less, more preferably 14% or less, further preferably 13% or less, from the viewpoint of balance with strength and the like.

The automobile electric wire has the aluminum alloy strand. Specifically, the automobile electric wire may be configured to include the aluminum alloy strand and the insulator covered on the outer periphery of the aluminum alloy strand.

The insulator may be composed of a resin composition containing as main components a polymer such as various resins and rubber (including an elastomer) having electric insulation. The resin or rubber may be used alone or in combination of two or more. Specific examples of the polymer include a vinyl chloride resin, a polyolefin resin, a polysulfone resin, a fluorine resin, and a fluorine rubber. The insulator may be composed of one layer or two or more layers. The thickness of the insulator may be, for example, 0.1 mm or more and 0.4 mm or less. The insulator may contain one or more kinds of additives generally used for electric wires. Examples of the additive include fillers, flame retardants, antioxidants, antioxidants, lubricants, plasticizers, antifouling agents, pigments, and the like.

Specifically, the automotive electric wire can be suitably used, for example, in an engine. This is because an automobile engine vibrates at a high temperature, and a high terminal fixing force is required.

The wire harness has the automobile electric wire and the terminal pressed on the aluminum alloy wire of the automobile electric wire. Specifically, in the wire harness, the terminal may be configured such that the cover of the wire terminal portion of the automobile electric wire is peeled off and pressed on the exposed aluminum alloy wire. Specifically, the wire harness may be configured such that a bundle of electric wires made up of a plurality of automotive wires is covered with a protective material.

The method for producing the aluminum alloy strand has the casting process, the wire drawing process, the drawing process, and the twisting process described above.

In the casting process, casting may be carried out by any of casting methods such as continuous casting using movable molds or frame-shaped fixed molds, and casting of a mold using a box-shaped fixed mold (hereinafter, sometimes referred to as billet casting) . Particularly, in the continuous casting, since the molten metal can be rapidly solidified and solidified, there is an advantage that a cast material having a fine crystal structure can be obtained. In addition, the rapid solidification makes it possible to obtain a cast material having a crystal structure in which fine precipitates are uniformly dispersed, as well as fine crystals are easily formed. By using such a cast material as a raw material, it becomes easy to produce an aluminum alloy strand having an aluminum alloy strand having a fine crystal structure. Therefore, in this case, it is possible to improve the strength of the aluminum alloy stranded wire due to refinement of the crystal and to improve the drawing workability at the time of manufacturing the aluminum alloy stranded wire.

In the whole-body process, for example, hot or cold rolling or extrusion may be employed as the plastic working. The whole body process is preferably a process for forming a rolled material by subjecting the cast material to hot rolling. In the case of using a billet casting material as a casting material, it is preferable to carry out a post-casting heat treatment (homogenizing treatment). The casting process and the whole body process are preferably carried out continuously. In this case, it is possible to easily carry out the plastic working such as hot rolling using the heat accumulated in the cast material. In this case, in this case, not only the energy efficiency is good but also the productivity is superior to the case where the two processes are performed in a batch manner.

In the drawing process, the drawing process can be specifically cold drawing process. The drawing degree can be changed by appropriately performing an intermediate softening treatment according to a desired line diameter. Further, in the above-described method for producing an aluminum alloy strand, the surface roughness Ra of the drawing material by a non-contact type surface roughness tester of a drawing material can be set to 0.15 탆 or more and 2 탆 or less by drawing. In this case, more specifically, the surface roughness Ra of the drawing material can be adjusted by controlling the roughness of the surface of the die used in the drawing process.

Further, in the method for producing an aluminum alloy strand, the surface roughness Ra of the drawn material after the drawing process may be less than 0.15 탆. In this case, after the drawing process, before the drawing wire is formed, a roughening treatment is performed with respect to the drawing material so that the surface roughness Ra is 0.15 탆 or more and 2 탆 or less. As the roughening treatment, specifically, for example, a mechanical technique, a chemical technique, and an electrical technique may be applied. These may be combined in one or two or more. Examples of the mechanical roughening treatment include a blast treatment, a polishing treatment, and a transfer with a rough roll on the surface. Examples of the chemical roughening treatment include etching with an alkaline solution such as a solution containing NaOH, etching with an acidic solution containing sulfuric acid, chromic acid, hydrofluoric acid, and the like. Examples of the cotton processing include electrolytic etching using an electrolytic solution such as a saline solution.

In the twisting process, a predetermined number of drawing members may be twisted together so as to obtain an aluminum alloy strand having a desired number of aluminum alloy strands. The heat treatment in the twisting process may be specifically softening treatment and / or aging treatment. The heat treatment can be carried out, for example, in an atmosphere of air or a non-oxidizing atmosphere. Examples of the non-oxidizing atmosphere include an atmosphere of vacuum, an inert gas (nitrogen, argon, etc.), a reducing gas (hydrogen containing gas, carbon dioxide gas containing gas) and the like. The heat treatment is preferably carried out in a non-oxidizing atmosphere with a small oxygen content in order to suppress generation of an oxide film on the surface of the drawing material provided in the twisted wire. In the twisting process, the heat treatment is preferably performed so that the tensile strength of the drawn wire is preferably 200 MPa or more and 350 MPa or less, and the elongation of the drawn wire is preferably 6% to 15% or less. It is easy to obtain an aluminum alloy strand having a tensile strength of not less than 200 MPa and not more than 350 MPa and a stretch elongation of not less than 6% and not more than 15%.

The heat treatment may be either batchwise or continuous. It is also possible to combine these methods. The continuous heat treatment is a treatment method for continuously heating the wire material. Since it can be continuously heated, the workability is excellent and the wire can be uniformly heated in the longitudinal direction thereof. Therefore, And the like.

Examples of the continuous heat treatment method include a direct energization method (energization continuous softening treatment) for heating an object to be heated through resistance heating, an indirect energization method (high frequency induction heating continuous softening treatment for heating an object to be heated through high frequency electromagnetic induction) ), A furnace system in which a heating object is introduced into a heating vessel (pipe softening furnace, etc.) in a heating atmosphere and heated by heat conduction, and the like. In the continuous heat treatment method, the linear velocity, the heat quantity, and the like can be appropriately adjusted so that the elongation of the drawn wire is in the above-mentioned range.

The heat treatment conditions in the batch type heat treatment may be, for example, a heating temperature of 140 ° C or more and 250 ° C or less, and a holding time of 4 hours or more and 16 hours or less.

In addition, each of the above-described constitutions can be arbitrarily combined as necessary in order to obtain the respective action effects and the like.

Example

(Example 1)

Examples of the aluminum alloy wire, the aluminum alloy wire and the manufacturing method thereof, the automobile wire and the wire harness will be described together with a comparative example.

<Aluminum alloy wire, aluminum alloy wire>

A pure aluminum ingot as a base was dissolved in a melting furnace. Pure aluminum ingots have a purity of more than 99.7%. The additive elements shown in Table 1 were added to the melting furnace so as to have the content (mass%) shown in Table 1, thereby preparing an aluminum alloy melt. Ti and Ti and B were adjusted by supplying Ti particles or TiB ₂ wires to an aluminum alloy melt immediately before casting as described below so as to have the contents shown in Table 1. [ Further, the aluminum alloy melt subjected to the component adjustment was subjected to hydrogen gas removal treatment and foreign matter removal treatment as appropriate.

A wire rod having a chemical composition of? 9.5 mm and a chemical composition shown in Table 1 was produced by continuously casting and hot-rolling an aluminum alloy melt using a belt-wheel continuous casting mill.

Next, the obtained wire rod was subjected to cold drawing using a predetermined die, and subjected to an intermediate softening treatment or an intermediate softening treatment as shown in Table 1, Thereby forming a wire drawing material.

With respect to the obtained drawing material, the surface roughness Ra was measured using a non-contact type surface roughness tester ("New View 1100", manufactured by zygo). Specifically, the measurement is performed by a laser microscope of a non-contact type surface roughness tester, after converting a planar roughness equivalent to a circle obtained from a drawing material into a plane (equivalent to a plane), and then calculating an arithmetic mean deviation Respectively. The number of test samples is n = 3 and the measurement area is 85 x 64 탆.

As a result, the freshness of the samples 1 to 5 and the sample 6-5 had a surface roughness Ra of not less than 0.15 mu m and not more than 2 mu m after the drawing process.

On the other hand, the fresh material of the sample whose surface roughness Ra after the drawing process was less than 0.15 탆 was subjected to surface roughening treatment separately. Specifically, Sample 6-1 was subjected to a roughening treatment of immersing in a 40% by mass aqueous solution of NaOH for 30 seconds. Sample 6-2 was subjected to a roughening treatment in which 10% by mass NaOH aqueous solution was immersed for 30 seconds. Sample 6-3 was subjected to a roughening treatment in which it was immersed in an aqueous 1% by weight NaOH solution for 30 seconds. The sample 6-4 was subjected to a surface-roughening treatment in which electrolytic etching (0.2 A) was carried out using 5 mass% of saline for 30 seconds. Sample 6-101 was roughened by immersing it in a 60% by mass aqueous solution of NaOH for 60 seconds. The surface roughness Ra after the drawing process was less than 0.15 mu m for the samples 6-102, samples 1-101 and samples 1-102, but the surface roughening treatment was not performed for comparison.

Next, each drawn material (each aluminum alloy wire) obtained was twisted at a number of twists and twist pitches of 24 mm shown in Table 1 to form respective wire rods. Thereafter, each of the drawn wires was subjected to heat treatment at a temperature shown in Table 1. Thus, each aluminum alloy strand was obtained. It is also possible to obtain each aluminum alloy wire by returning the twist of each aluminum alloy wire.

<Automotive wires>

Polyvinyl chloride (PVC) as an insulator was extruded and coated on the outer periphery of the resulting conductor made of aluminum alloy strands to a thickness shown in Table 1. [ Thus, electric wires for each vehicle were obtained.

<Wire harness>

The insulator 20 at the wire end portion of the automobile electric wire 2 was peeled off and the terminal 30 was pressed against the exposed conductor (aluminum alloy strand 1) as shown in Fig. The terminal 30 has a wire barrel 301 for fixing the aluminum alloy wire 1 as a conductor of the automotive electric wire 2 and an insulation barrel 302 for fixing the insulator 20 thereto. In Fig. 1, reference numeral 10 denotes an aluminum alloy strand. The terminal 30 is pressed by plastic deformation of each of the barrels 301 and 302 using a mold of a predetermined shape not shown. In this example, as shown in Fig. 2, the terminals 30 are all pressed under the condition that the crimp height (C / H) (compression ratio) is 60%. In Fig. 2, the aluminum alloy wire is omitted. Thus, the respective wire harnesses 3 were obtained.

(Tensile Strength and Elongation of Aluminum Alloy Strand)

The tensile strength (MPa) and elongation (%) of the aluminum alloy strand were measured by conducting a tensile test on the aluminum alloy stranded wire as the conductor obtained in the present example under the conditions of the inter-strand distance GL = 250 mm and the tensile rate 50 mm / ) Were measured.

(Measurement of terminal fixing force)

The terminal fixing force was measured using a wire harness automobile wire. More specifically, the automobile electric wire is tensioned at a tensile speed of 100 mm / min while the terminal is fixed by using the automobile electric wire to which the terminal is compressed, the maximum load N at which the terminal is not released is measured, This was regarded as a terminal fixing force. In addition, the diameter of each strand is different. Therefore, the ratio of the terminal fastening force to the conductor breakage load N measured by the above-described tensile test was calculated.

Table 1 shows the detailed composition of each aluminum alloy wire, each aluminum alloy wire, each automobile wire, and each wire harness. Table 2 shows the surface roughness Ra of each aluminum alloy wire, the tensile strength and elongation of each aluminum alloy wire, and the ratio of terminal fastening force / conductor breakage load.

As shown in Tables 1 and 2, in Sample 1 to Sample 6-5, the aluminum alloy strand has a specific chemical composition and the surface roughness Ra of the aluminum alloy strand is within a specific range. For this reason, Sample 1 to Sample 6-5 were able to improve the terminal fixing force. This is because when the surface of the aluminum alloy strand having a specific chemical composition has a surface roughness Ra in a specific range, the frictional force between the aluminum alloy strands existing in the inner strand of the aluminum alloy strand And the sliding of the aluminum alloy element wires is suppressed. As a result, the aluminum alloy element wire of the inner layer is hardly released.

In contrast to these, in the samples 1-101 and 1-102, the aluminum alloy strand has no specific chemical composition and the surface roughness Ra of the aluminum alloy strand is not within the specified range. For this reason, the samples 1-101 and 1-102 could not improve the terminal fixing force.

In the sample 6-101, the aluminum alloy wire has a specific chemical composition, but the surface roughness Ra of the aluminum alloy wire is more than 2 占 퐉. For this reason, the sample 6-101 could not improve the terminal fixing force.

In Sample 6-102, the aluminum alloy strand has a specific chemical composition, but the surface roughness Ra of the aluminum alloy strand is less than 0.15 mu m. For this reason, Samples 6-102 could not improve the terminal fixing force.

Although the embodiments of the present invention have been described in detail, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the present invention.

Claims (9)

An aluminum alloy wire used for a conductor of an automobile electric wire,
0.3% by mass or more and 0.9% by mass or less of Mg,
Si: 0.1 mass% or more and 0.7 mass% or less,
Fe: 0.1 mass% or more and 0.4 mass% or less,
At least one element selected from the group consisting of Cu, Cr, Ni and Zr: 0.01 mass% or more and 0.5 mass% or less in total
&Lt; / RTI &gt;
The remainder having a chemical composition of Al and inevitable impurities,
Wherein the surface roughness Ra of the non-contact type surface roughness tester is in the range of 0.15 탆 to 2 탆. The method of claim 1, wherein the chemical composition further comprises Ti, B, or both,
The Ti content is 0.003 mass% or more and 0.03 mass% or less,
And the B content is 0.0003 mass% or more and 0.003 mass% or less. The aluminum alloy strand according to claim 1 or 2, wherein the wire diameter is 0.1 mm or more and 0.4 mm or less. An aluminum alloy strand according to any one of claims 1 to 3, wherein a plurality of aluminum alloy strands are twisted together. The aluminum alloy strand according to claim 4, wherein the tensile strength is 200 MPa or more and 350 MPa or less. The aluminum alloy strand according to claim 4, wherein the number of strands of the aluminum alloy strand is one selected from the group consisting of 7, 11, 19 and 37. The aluminum alloy strand according to claim 4
And an electric wire for an automobile. An automotive electric wire according to claim 7,
A terminal pressed against the aluminum alloy strand of the automobile wire
And a wire harness. A method of manufacturing an aluminum alloy strand used in a conductor of an automobile electric wire,
0.3% by mass or more and 0.9% by mass or less of Mg,
Si: 0.1 mass% or more and 0.7 mass% or less,
Fe: 0.1 mass% or more and 0.4 mass% or less,
At least one element selected from the group consisting of Cu, Cr, Ni and Zr: 0.01 mass% or more and 0.5 mass% or less in total
&Lt; / RTI &gt;
A casting step of forming a casting material having a chemical component composition consisting of Al and inevitable impurities,
A whole body process for forming a body material by subjecting the cast material to a plastic working process,
A drawing step of forming a drawing material by drawing on the whole body material,
A twisting process in which a plurality of the drawing members are twisted to form a drawing member, heat treatment is applied to the drawing member, or a heat treatment is performed on the drawing member, and a plurality of the heat-
Lt; / RTI &
By the above drawing process, the surface roughness Ra of the drawing material measured by the non-contact type surface roughness measuring device is set to 0.15 탆 or more and 2 탆 or less,
Wherein the surface roughness Ra of the drawing material is 0.15 탆 or more and 2 탆 or less by the non-contact type surface roughness tester after the drawing process, before forming the drawing material. Way.

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